diff options
Diffstat (limited to 'krebs/3modules/backup.nix')
| -rw-r--r-- | krebs/3modules/backup.nix | 138 |
1 files changed, 57 insertions, 81 deletions
diff --git a/krebs/3modules/backup.nix b/krebs/3modules/backup.nix index d22dd3810..71b22d8cb 100644 --- a/krebs/3modules/backup.nix +++ b/krebs/3modules/backup.nix @@ -103,103 +103,91 @@ let plan.method == method && config.krebs.build.host.name == plan.${side}.host.name; - start = plan: pkgs.writeDash "backup.${plan.name}" '' + start = plan: let + login-name = "root"; + identity = local.host.ssh.privkey.path; + ssh = "ssh -i ${shell.escape identity}"; + local = getAttr plan.method { + push = plan.src // { rsync = src-rsync; }; + pull = plan.dst // { rsync = dst-rsync; }; + }; + remote = getAttr plan.method { + push = plan.dst // { rsync = dst-rsync; }; + pull = plan.src // { rsync = src-rsync; }; + }; + src-rsync = "rsync"; + dst-rsync = concatStringsSep " && " [ + "stat ${shell.escape plan.dst.path} >/dev/null" + "mkdir -m 0700 -p ${shell.escape plan.dst.path}/current" + "flock -n ${shell.escape plan.dst.path} rsync" + ]; + in pkgs.writeScript "backup.${plan.name}" '' + #! ${pkgs.bash}/bin/bash set -efu + start_date=$(date +%s) + ssh_target=${shell.escape login-name}@$(${fastest-address remote.host}) ${getAttr plan.method { push = '' - identity=${shell.escape plan.src.host.ssh.privkey.path} - src_path=${shell.escape plan.src.path} - src=$src_path - dst_user=root - dst_host=$(${fastest-address plan.dst.host}) - dst_port=$(${network-ssh-port plan.dst.host "$dst_host"}) - dst_path=${shell.escape plan.dst.path} - dst=$dst_user@$dst_host:$dst_path - echo "update snapshot: current; $src -> $dst" >&2 - dst_shell() { - exec ssh -F /dev/null \ - -i "$identity" \ - ''${dst_port:+-p $dst_port} \ - "$dst_user@$dst_host" \ - -T "$with_dst_path_lock_script" - } - rsh="ssh -F /dev/null -i $identity ''${dst_port:+-p $dst_port}" - local_rsync() { - rsync "$@" - } - remote_rsync=${shell.escape (concatStringsSep " && " [ - "mkdir -m 0700 -p ${shell.escape plan.dst.path}/current" - "exec flock -n ${shell.escape plan.dst.path} rsync" - ])} + rsync_src=${shell.escape plan.src.path} + rsync_dst=$ssh_target:${shell.escape plan.dst.path} + echo >&2 "update snapshot current; $rsync_src -> $rsync_dst" ''; pull = '' - identity=${shell.escape plan.dst.host.ssh.privkey.path} - src_user=root - src_host=$(${fastest-address plan.src.host}) - src_port=$(${network-ssh-port plan.src.host "$src_host"}) - src_path=${shell.escape plan.src.path} - src=$src_user@$src_host:$src_path - dst_path=${shell.escape plan.dst.path} - dst=$dst_path - echo "update snapshot: current; $dst <- $src" >&2 - dst_shell() { - eval "$with_dst_path_lock_script" - } - rsh="ssh -F /dev/null -i $identity ''${src_port:+-p $src_port}" - local_rsync() { - mkdir -m 0700 -p ${shell.escape plan.dst.path}/current - flock -n ${shell.escape plan.dst.path} rsync "$@" - } - remote_rsync=rsync + rsync_src=$ssh_target:${shell.escape plan.src.path} + rsync_dst=${shell.escape plan.dst.path} + echo >&2 "update snapshot current; $rsync_dst <- $rsync_src" ''; }} - # Note that this only works because we trust date +%s to produce output - # that doesn't need quoting when used to generate a command string. - # TODO relax this requirement by selectively allowing to inject variables - # e.g.: ''${shell.quote "exec env NOW=''${shell.unquote "$NOW"} ..."} - with_dst_path_lock_script="exec env start_date=$(date +%s) "${shell.escape - "flock -n ${shell.escape plan.dst.path} /bin/sh" - } - local_rsync >&2 \ + ${local.rsync} >&2 \ -aAXF --delete \ - --rsh="$rsh" \ - --rsync-path="$remote_rsync" \ - --link-dest="$dst_path/current" \ - "$src/" \ - "$dst/.partial" - dst_shell < ${toFile "backup.${plan.name}.take-snapshots" '' + --rsh=${shell.escape ssh} \ + --rsync-path=${shell.escape remote.rsync} \ + --link-dest=${shell.escape plan.dst.path}/current \ + "$rsync_src/" \ + "$rsync_dst/.partial" + + dst_exec() { + ${getAttr plan.method { + push = ''exec ${ssh} "$ssh_target" -T "exec$(printf ' %q' "$@")"''; + pull = ''exec "$@"''; + }} + } + dst_exec env \ + start_date="$start_date" \ + flock -n ${shell.escape plan.dst.path} \ + /bin/sh < ${toFile "backup.${plan.name}.take-snapshots" '' set -efu : $start_date - dst=${shell.escape plan.dst.path} + dst_path=${shell.escape plan.dst.path} - mv "$dst/current" "$dst/.previous" - mv "$dst/.partial" "$dst/current" - rm -fR "$dst/.previous" + mv "$dst_path/current" "$dst_path/.previous" + mv "$dst_path/.partial" "$dst_path/current" + rm -fR "$dst_path/.previous" echo >&2 snapshot() {( : $ns $format $retain name=$(date --date="@$start_date" +"$format") - if ! test -e "$dst/$ns/$name"; then + if ! test -e "$dst_path/$ns/$name"; then echo >&2 "create snapshot: $ns/$name" - mkdir -m 0700 -p "$dst/$ns" + mkdir -m 0700 -p "$dst_path/$ns" rsync >&2 \ -aAXF --delete \ - --link-dest="$dst/current" \ - "$dst/current/" \ - "$dst/$ns/.partial.$name" - mv "$dst/$ns/.partial.$name" "$dst/$ns/$name" + --link-dest="$dst_path/current" \ + "$dst_path/current/" \ + "$dst_path/$ns/.partial.$name" + mv "$dst_path/$ns/.partial.$name" "$dst_path/$ns/$name" echo >&2 fi case $retain in ([0-9]*) delete_from=$(($retain + 1)) - ls -r "$dst/$ns" \ + ls -r "$dst_path/$ns" \ | sed -n "$delete_from,\$p" \ | while read old_name; do echo >&2 "delete snapshot: $ns/$old_name" - rm -fR "$dst/$ns/$old_name" + rm -fR "$dst_path/$ns/$old_name" done ;; (ALL) @@ -227,24 +215,12 @@ let | ${pkgs.coreutils}/bin/head -1; } ''; - # Note that we don't escape word on purpose, so we can deref shell vars. - # TODO type word - network-ssh-port = host: word: '' - case ${word} in - ${concatStringsSep ";;\n" (mapAttrsToList - (_: net: "(${head net.aliases}) echo ${toString net.ssh.port}") - host.nets)};; - esac - ''; - in out # TODO ionice -# TODO mail on failed push, pull # TODO mail on missing push # TODO don't cancel plans on activation # also, don't hang while deploying at: # starting the following units: backup.wu-home-xu.push.service, backup.wu-home-xu.push.timer -# TODO make sure /bku is properly mounted # TODO make sure that secure hosts cannot backup to insecure ones # TODO optionally only backup when src and dst are near enough :) # TODO try using btrfs for snapshots (configurable) |